no need to download composer via curl
add MultipleUseStatementFixer
minor #474 [minor] simplify Travis (keradus)

This PR was merged into the 0.5.x-dev branch.

Discussion
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[minor] simplify Travis

No need to download composer installer via curl and install it by php.
Just to save few secs on Travis jobs

Commits
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19e3229 no need to download composer via curl
feature #480 [feature]Multiple use fixer. (keradus)

This PR was merged into the 0.5.x-dev branch.

Discussion
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[feature]Multiple use fixer.

Multiple use fixer.
As requested: #140

Commits
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be3fc99 add MultipleUseStatementFixer
enhance priority testing
minor #481 enhance priority testing (keradus)