e and pi: defined as functions but not as processes

[soxofaan]

e and pi are defined as functions, but not as @process:

openeo-processes-python/src/openeo_processes/math.py

Lines 20 to 44 in 58a547e

	def e():
	"""
	The real number e is a mathematical constant that is the base of the natural logarithm such that ln(e) = 1.
	The numerical value is approximately 2.71828.
	Returns
	-------
	float :
	The numerical value of Euler's number.
	"""
	return np.e
	def pi():
	"""
	The real number Pi (π) is a mathematical constant that is the ratio of the circumference of a circle to its
	diameter. The numerical value is approximately 3.14159.
	Returns
	-------
	float :
	The numerical value of Pi.
	"""
	return np.pi

which means they are bit harder to integrate with "lookup process by name" (e.g. #10/#13)

[soxofaan]

likewise, the text functions (text_begins, ...) are also not defined as @process and not reachable through util.get_process()

openeo-processes-python/src/openeo_processes/texts.py

Lines 1 to 2 in a0cf455

	def text_begins(text, pattern, case_sensitive=True):