Short circuit parsing when label matchers are present

[MasslessParticle]

This PR makes parsers aware of any downstream label-matcher stages at parse time. As labels are parsed, if one has a matcher, the matcher is checked at parse time. If the label does not match it's matcher, parsing is halted on that log line.

ex 1:
consider the log:
foo=1 bar=2 baz=3

And the query
{} | logfmt | bar=3

When bar is parsed it is immediately checked against it's matcher. The match fails so we the parser never spends time parsing the rest of the line.

ex 2:
consider the log:
foo=1 baz=3 bletch=4

And the query
{} | logfmt | bar=3

bar is never seen in the log so the whole line is parsed.

Benchmarks:

                                                   │ parsers__old_2.txt │          parsers__new_3.txt          │
                                                   │       sec/op       │    sec/op     vs base                │
_Parser/json/inline_stages-8                              3413.5n ±  5%    766.4n ± 4%  -77.55% (p=0.000 n=10)
_Parser/jsonParser-not_json_line/inline_stages-8           101.5n ±  6%    103.1n ± 8%        ~ (p=0.645 n=10)
_Parser/unpack/inline_stages-8                             383.8n ±  4%    388.0n ± 9%        ~ (p=0.954 n=10)
_Parser/unpack-not_json_line/inline_stages-8               13.30n ±  2%    13.11n ± 1%        ~ (p=0.247 n=10)
_Parser/logfmt/inline_stages-8                            2105.5n ± 16%    727.7n ± 4%  -65.44% (p=0.000 n=10)
_Parser/regex_greedy/inline_stages-8                       4.220µ ±  4%    4.175µ ± 4%        ~ (p=0.739 n=10)
_Parser/regex_status_digits/inline_stages-8                319.8n ±  5%    326.4n ± 8%        ~ (p=0.481 n=10)
_Parser/pattern/inline_stages-8                            185.2n ±  7%    154.2n ± 3%  -16.74% (p=0.000 n=10)

                                                   │ parsers__old_2.txt │          parsers__new_3.txt          │
                                                   │        B/op        │    B/op     vs base                  │
_Parser/json/inline_stages-8                              280.00 ± 0%     64.00 ± 0%  -77.14% (p=0.000 n=10)
_Parser/jsonParser-not_json_line/inline_stages-8           16.00 ± 0%     16.00 ± 0%        ~ (p=1.000 n=10) 
_Parser/unpack/inline_stages-8                             80.00 ± 0%     80.00 ± 0%        ~ (p=1.000 n=10) 
_Parser/unpack-not_json_line/inline_stages-8               0.000 ± 0%     0.000 ± 0%        ~ (p=1.000 n=10) 
_Parser/logfmt/inline_stages-8                            336.00 ± 0%     74.00 ± 0%  -77.98% (p=0.000 n=10)
_Parser/regex_greedy/inline_stages-8                       193.0 ± 1%     192.0 ± 1%        ~ (p=0.656 n=10)
_Parser/regex_status_digits/inline_stages-8                51.00 ± 0%     51.00 ± 0%        ~ (p=1.000 n=10) 
_Parser/pattern/inline_stages-8                           35.000 ± 0%     3.000 ± 0%  -91.43% (p=0.000 n=10)

                                                   │ parsers__old_2.txt │          parsers__new_3.txt          │
                                                   │     allocs/op      │ allocs/op   vs base                  │

_Parser/json/inline_stages-8                              18.000 ± 0%     4.000 ± 0%  -77.78% (p=0.000 n=10)
_Parser/jsonParser-not_json_line/inline_stages-8           1.000 ± 0%     1.000 ± 0%        ~ (p=1.000 n=10) 
_Parser/unpack/inline_stages-8                             4.000 ± 0%     4.000 ± 0%        ~ (p=1.000 n=10) 
_Parser/unpack-not_json_line/inline_stages-8               0.000 ± 0%     0.000 ± 0%        ~ (p=1.000 n=10) 
_Parser/logfmt/inline_stages-8                            16.000 ± 0%     6.000 ± 0%  -62.50% (p=0.000 n=10)
_Parser/regex_greedy/inline_stages-8                       2.000 ± 0%     2.000 ± 0%        ~ (p=1.000 n=10) 
_Parser/regex_status_digits/inline_stages-8                2.000 ± 0%     2.000 ± 0%        ~ (p=1.000 n=10) 
_Parser/pattern/inline_stages-8                            2.000 ± 0%     1.000 ± 0%  -50.00% (p=0.000 n=10)