Extend Timeseries class for MQL4/MQL5 compability.

[kenorb]

Write, extend and correct the existing Timeseries class in order to implement cross-version methods which should correspond to Timeseries Functions from MQL4. Similar to #1, #2 & #3.

Each method should compile, be callable and should return same format and values in both MQL4 and MQL5. Remove all other functions which are not mentioned on the list.

In case of blockers, create a method placeholders with todo comments.

See: porting table for some guidance.

[kenorb]

PR: #6