21 fix unroll issue

[scnerd]

Resolves #21

• Fixes issue where ast.Index has been deprecated an, in general, replaced simply by the underlying value it wrapped.
• Fixes test bug with .lift keeping source file open and locked.
• Add bump2version support to simplify bumping the version.

[coveralls]

Pull Request Test Coverage Report for Build 161

• 26 of 29 (89.66%) changed or added relevant lines in 5 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-0.2%) to 85.586%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pragma/collapse_literals.py	0	1	0.0%
pragma/unroll.py	0	1	0.0%
pragma/utils.py	22	23	95.65%

Files with Coverage Reduction	New Missed Lines	%
pragma/core/init.py	1	94.12%

Totals
Change from base Build 158:	-0.2%
Covered Lines:	1241
Relevant Lines:	1450

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💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 163

• 28 of 29 (96.55%) changed or added relevant lines in 5 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.1%) to 85.862%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pragma/utils.py	22	23	95.65%

Totals
Change from base Build 158:	0.1%
Covered Lines:	1245
Relevant Lines:	1450

---

💛 - Coveralls