feat(frontends/lean/builtin_cmds): add 'print prefix' command
feat(frontends/lean/structure_cmd): generate projection over constructor theorems for structures
chore(bin/lmake): remove
chore(src/CMakeLists.txt): copy linja and ltag to bin when install
fix(emacs/lean-mode): handle when there is spaces in filenames
feat(src/emacs/lean-mode): add shortcut for restarting lean server
refactor(frontends/lean): combine info annotations in a single module
fix(frontends/lean): type information for "atomic" notation declaration, fixes #292
refactor(frontends/lean/local_context): add 'const' modifier
fix(frontends/lean/placeholder_elaborator): local context must be adjusted when performing class-instance resolution modulo Pi-abstraction, fixes #293
fix(library/hott) fix funext.lean by making funext an instance
chore(library/hott) move theorem about precomposition to its own file
feat(library/hott) add theorem: assuming function extensionality, precomposing and postcomposing of equivalences is an equivalence
fix(frontends/lean/structure_cmd): universe level validation
fix(emacs/lean-mode.el): remove quotation marks in lean-execute

Close #294
feat(frontends/lean): add 'record' as an alias for 'structure' command
fix(frontends/lean/structure_cmd): error parsing structure without parameters followed by ': Type'
fix(frontends/lean/structure_cmd): accept ': Type' when universe levels are not specified
fix(frontends/lean/structure_cmd): bad test output
feat(library/hott) add theorem: if f is an equivalence, so is ap f