Calcium 1.5.0

By @NriotHrreion

Add

• Calculator input content highlighting
• Currency exchanging dialog

Improve

• Code readability

Change

• Add some blue style as highlighter
• Use InputContext to manage inputting data

Fix

• Unexpected position of coordinate line number in graphing mode
• Unexpected colors of brackets of function symbol
• phi is not a number
• Variables set during the calculations of sum, product and integral are not deleted when the calculations finish
• InputBox won't update when the exponential changes
• $29.4^2 \neq 864.36$
• Uncomfortable auto completing of brackets
• Function wrapped with brackets outside cannot be graphed (#16)
• Incorrect calculations of integration that have negative limits (#17)
• Selector cannot select the default value
• Non-numbers can be inputted by pasting into currency input

Other

• Some grammar correction and some changes to README